Setting of Thin Set and Thick Set

[Yasushi Morikawa]

Hi, all,

 

I’m running a python API (OpenVSP v3.51.3 on MacOS) for the model which include a wing, a fuselage and actuator disks.

But I can’t calculate successfully, because the parameters of the actuator disks can’t be set.

 

The wing and fuselage are set in set_0, the actuator disks set in set_1.

And I try to compute with wing and fuselage as Thick and actuator disks as Thin. 

As a result of run, Actuator disk ID was found, however parm IDs such as RotorRPM were not found.

 

 

The error messages are as follows.

 

Disk #0 found as JEKPTGFGFA 

Error Code: 4, Desc: FindParm::Can't Find Parm RotorRPM Rotor

Error Code: 4, Desc: SetParmVal::Can't Find Parm 

Error Code: 4, Desc: FindParm::Can't Find Parm RotorCP Rotor

Error Code: 4, Desc: SetParmVal::Can't Find Parm 

Error Code: 4, Desc: FindParm::Can't Find Parm RotorCT Rotor

Error Code: 4, Desc: SetParmVal::Can't Find Parm

 

 

The part of my code is as follows.

 

analysis_name = 'VSPAEROSweep'

vsp.SetAnalysisInputDefaults(analysis_name)

wid = vsp.FindGeomsWithName('WingGeom')

vsp.SetIntAnalysisInput(analysis_name, 'RefFlag', (ref_flag := [1]), 0)

vsp.SetStringAnalysisInput(analysis_name, 'WingID', wid, 0)

vsp.SetIntAnalysisInput(compgeom_name, 'GeomSet', [vsp.SET_FIRST_USER + 0], 0)

vsp.SetIntAnalysisInput(compgeom_name, 'ThinGeomSet', [vsp.SET_FIRST_USER + 1], 0)

 

   …

 

for rotor in range(ndisk):

        id = vsp.FindActuatorDisk(rotor)

        rev = rt_perf_tbl[aoa][rotor]['rev']

        ct = rt_perf_tbl[aoa][rotor]['ct']

        cp = rt_perf_tbl[aoa][rotor]['cp']

        print(f'\nDisk #{rotor} found as {id:s} ') #rev={rev:5g} Cp={cp:.6g} Ct={ct:.6g}')

        vsp.SetParmVal(vsp.FindParm(id, 'RotorRPM', 'Rotor'), float(rev))

        vsp.SetParmVal(vsp.FindParm(id, 'RotorCP', 'Rotor'), cp)

        vsp.SetParmVal(vsp.FindParm(id, 'RotorCT', 'Rotor'), ct)

 

 

I don’t know where I’m making a mistake in my code.

Please give me some advice.

Thanks.

[Rob McDonald]

Look at 

examples/scripts/VSPAERO_ActuatorDisk_CSGroup.vspscript

I think it shows how to set up an actuator disk for VSPAERO from the scripting environment.  Although this script is in vspscript, it is pretty much a 1:1 translation to Python.

Rob

[Yasushi Morikawa]

Thank you for your reply.

 

I tried to improve my script by referring VSPAERO_ActuatorDisk_CSGroup.vspscript.

But I can’t solve my problem.

 

Is there a problem with the vsp3 file?

 

I would greatly appreciate it if you could check my files.

 

Thanks,

2026年9月19日土曜日 23:38:23 UTC+9 Rob McDonald:

[Rob McDonald]

I don't really recommend the actuator disk mode in nearly hover.  You may be able to get some result from it, but it really is meant for conventional aircraft in cruise.

I would put the wing in the thin set.  It doesn't have to be, but it works really well.

If you are blowing the wing with the actuator disk, you'll need to increase the spanwise resolution of the wing such that you have multiple mesh points across the disk -- I would aim for at least five on each half of the disk.  This is a lot more resolution than a normal cruise case would need.

With Vinf=20, your actuator disk settings result in eta=1.9 -- which is clearly not physical.  I suggest you use the radio buttons to change your settings to be based on RPM, Thrust, and eta -- that way it is easy to dial in a physically meaningful set of parameters.

In general, I recommend people use a Stack instead of a Fuselage.

I did not look at your script.  I did play with your model and found no major problems other than the above suggestions.  I made those changes and things seemed to work fine.

Rob

[Yasushi Morikawa]

Thank you for your suggestion.

 

The model test01.vsp3 is a file for testing my script.

It is different from the model that will actually be calculated.

I will improve my model by referring your suggestion.

 

My problem is setting of thin set, thick set and actuator disk parameters.

I can’t set the actuator disk parameters from the script at the moment.

 

I will continue to tackle the problem.

Please let me know if you find anything out about my script.

 

Thanks,

2026年9月21日月曜日 2:41:58 UTC+9 Rob McDonald: